"Keeping the drum" is basically what they do with all foreign objects they stole. This is trying to make it look like France is in favor of cultural independence, but they are constantly having the speech of "these inferior countries don't deserve to have their stuff back, they're too primitive for that"
If an article says "Trump hugs a black guy" you wouldn't see it as propaganda?
The point of advertising as positive, something that is supposed to be normal, to have been done long ago, and that is just an exception in the middle of a lot of shit, is propaganda, yes.
The goal is to show France as a nice, culturally aware country that respects other countries, while it does the exact opposite.
It's basically the same kind of manipulation as when the far right talks about wanting freedom of speech or being colorblind. It's trying to put a positive look on something negative to influence people into tolerating and normalising it.
"No, the nazis are not so extreme or racist, look, they gave back a drum that the country stole. They are being reasonable in the end"